In previous studies of the olfactory system, I found that statistical measures of extracellular field potentials can be used to characterize aspects of the functional topography of two cortical structures. I propose to apply similar but more advanced signal-processing analyses developed in human studies to field potentials from cortical regions that process visuomotor information in monkeys performing go/no-go visual pattern discrimination tasks. Patterns of field potential relationship (covariance or nonlinear measures) will be measured between multiple cortical regions during successive intervals from the visual stimulus through the response. These measurements will distinguish salient aspects of the topography and timing of the shifting, distributed cortical processing networks accompanying goal-directed behaviors. This research has the following potential benefits: (1) it may validate a new analytic tool for characterizing functional cortical processing networks; (2) new aspects of functional relations between cortical regions during visuomotor performance may be discovered; and (3) since the tasks employed closely resemble those used to study human event- related potential components, aspects of the neural basis of these phenomena may be elucidated.